Rack mounted electronic devices may be mounted to vertical rack columns such that a face of the electronic device extends slightly forward of the rack and the electronic device is supported by the vertical columns. In the case of equipment in which internal components are normally accessed, a cover or door may be used, such that the door can be opened without dismounting the equipment from the rack.
As described herein, the "rack mounted electronic device" is a complete component in a housing or case. It is anticipated that in many cases such a component will have little or no function unless associated with other components, and often such other components are mounted on the same or a different rack. The present invention was developed for use with computer disk drive assemblies.
In addition, some components are mounted within other components, such as disk drives within a disk drive housing. While this represents a different level of hardware assembly, the inventive concepts are the same and the invention is intended to cover such different levels of assembly.
Effects like radio frequency noise are of little concern during the time period of testing and assembly of racks of equipment. Additionally, during such assembly, there is a tendency for parts of various devices to accumulate and be lost or misidentified. Subsequent to assembly, radio frequency noise and physical shielding of electronic devices becomes more important. Therefore it is desirable that items like the door to a device remain with the device during this time. This avoids losing the door and also assures that it is not necessary to add the step of installing the door subsequent to assembly of the rack with its components, assuming the door can be identified in the first place. Since the door is on the device, it is not necessary for those later charged with supervising the rack of equipment appreciate the door's functional utility.
If the concealment of the mounting arrangement is accomplished by separate covers, it is often the case that the separate covers are either misplaced or not used. In addition to the possibility that those assembling the devices to the racks may see no point to installing the covers, often final completion of the rack is delayed, making it possible to misplace covers and the like in the interim.
It is desired to provide a door which mounts to an electronic device away from the center of the device and preferably at a location used for mounting the device to the rack columns. This places the door's mount at a location where the door and its mounts are best able to be positioned clear of the front of the device. It is further desired that the mounting arrangement for the door permit the door to hinge away from the front of the device to a maximum extent without extending beyond the frontal area of the device.
Ideally, the door should easily swing open to reveal a maximum frontal area of the component, and yet remain clear of other equipment. It may also be desired that the door be in a position which invites closing by the user. For aesthetic reasons, it is desired that the mounting hardware for the device to the rack and the door hinge assembly be concealed, thereby providing a "clean" appearance. It is also desired to conceal the mounting arrangements for the rack columns while facilitating easy mounting of the device to the rack.
The ability of the door to cover the entire face of the equipment is advantageous because the door is also used as an RFI shield for the equipment. By conveniently retaining the door, it is possible to assure that during normal operation, the door can be conveniently closed. It is desired that the hinge does not extend across the width of the door. This avoids the hinge interacting with electromagnetic fields, particularly if the hinge is formed of a ferromagnetic material. In addition, it may be desired to have the space along the hinge axis not be occupied by a hinge pin or other part of the hinge along the entire width of the device.
Hinge design, in addition to taking into consideration durability and cost, should provide the door with an ability to remain clear of the device which uses the hinge. In addition, the door should not extend beyond the height or width dimensions of the equipment in order that opening the door not be inhibited by other equipment.
In one arrangement for rack mounted equipment, mounting blocks or pillow blocks are used to mount the components to the rack columns. The mounting blocks in turn are fixed to the device. The mounting blocks are at the outer edges of the equipment, thereby making them advantageous locations for mounting hinges. It is desired, however, that assembly of the device to the rack columns be accomplished without disassembling the hinge.